1. Field of the Invention
This invention relates to a catalytic apparatus. More particularly, the invention relates to the construction of the catalyst bed filling portion of a parallel flow type denitration apparatus.
2. Description of the Prior Art
In a dry type exhaust gas denitration apparatus, a catalyst bed is formed in the passage of high temperature boiler exhaust gas and ammonia gas is injected upstream of the gas passage to remove nitrogen oxides from the exhaust gas passing through the catalyst bed by decomposing them into water and nitrogen. Out of such apparatuses, there is a parallel flow type denitration apparatus in which a catalyst bed of plate type of honey-comb type catalyst is formed and which is featured in that the pressure loss in the course of the gas passing through the catalyst bed is such that it can be covered with the surplus in fan capacity provided in the boiler design stage. Referring to FIG. 1, the exhaust gas G produced in boiler 1 is denitrated in the catalyst bed 5 formed between economizer exit and air heater 2 and is then released to the open air from stack 4 through air heater 2 and dust collector 3. The catalyst bed 5 is formed by piling up in duct D, as shown in FIG. 2, a number of catalyst elements 6 each consisting of a plurality of catalyst plates 16 spaced as shown in FIG. 3. That is, in duct D there is provided a catalyst supporting beam 14 on which grating 12 or the like is placed. Catalyst elements 6 are carried in duct D through hatch 13 using a transporting means 17 such as chain block or the like and are then piled up by the human power of workers to form catalyst bed 5. Therefore, much labor and time are required for carrying in and out of and refilling with catalyst. Further, individual catalyst elements 6 have to be placed one by one and, hence, there is the possibility of their being located out of position, in which case smooth passing of exhaust gas G is disturbed. Therefore, constant control is necessary for the catalyst bed.
It is an object of this invention to provide a catalytic apparatus which facilitates carrying in and out of and refilling with catalyst.
It is another object of the invention to provide a catalytic apparatus which allows the exhaust gas to pass easily and can keep the quality of catalyst bed excellent at all times.